A novel analysis of ZVS wireless power transfer system using coupled resonators

Two coils constitute a coupled-resonator wireless power transfer (WPT) system contributing as a critical part of zero-volt-switching (ZVS) power supply. Coupled resonators are first analyzed by the harmonic resonance analysis (HRA), and the F-parameter resonance analysis (FRA) methods to obtain the input impedance and voltage gain vs. the operating frequency. After that, the total circuit including the switching transistors and rectifying diodes is analyzed by the switching converter analysis tool (SCAT). The estimated voltage gain by the FRA method is well duplicated in the total zero volt switching (ZVS) circuit simulation including the semiconductor devices by SCAT. Thus, the coupled coil resonators analysis is for the first time utilized to analyze the total high-efficiency ZVS WPT system.